I still can't figure it out. Isn't there a surprise along with the construction kit's release?

Really? It's a free DLC with high resolution textures, go to the Skyrim store page and download it.

HD Texture DLC

http://store.steampowered.com/app/202485/

The HD Texture pack.
Bottom left of steam is a "+ Add a game..." link.
> Browse the steam store for games
> Genres >RPG
New Releases shows the "Skyrim: High Resolution Texture Pack (Free DLC)"